1. Field of the Invention
The present invention relates to ice making machines, more particularly to an ice making machine in which the ice forming unit includes an upright ice forming plate located above a water tank and having a cooling surface in a heat exchange relationship with an evaporator attached thereto and an ice forming surface to be supplied with water from the water tank by means of a water pump for forming the water into ice cubes.
2. Description of the Prior Art
In conventional ice making machines disclosed, for example, in Japanese Utility Model Publication No. 59-39571, Japanese Patent Early Publication No. 2-93266 and U.S. Pat. No. 4,341,087, the evaporator is arranged to be supplied with hot gas through a hot gas valve in the refrigeration system for defrost of the ice cubes formed on the ice forming plate. In conventional ice making machines disclosed, for example, in Japanese Utility Model Publication No. 57-49107 and U.S. Pat. No. 3,074,252, the evaporator is arranged to be exposed with fresh water supplied from a water supply pipe for defrost of the ice cubes formed on the ice forming plate. In conventional ice making machines disclosed, for example, in Japanese Patent Early Publication No. 62-210367, Japanese Patent Publication No. 64-7307 and U.S. Pat. No. 3,465,537, the evaporator is arranged to be supplied with hot gas through a hot gas valve in the refrigeration system and exposed with fresh water supplied from a water supply pipe for defrost of the ice cubes formed on the ice forming plate.
In such conventional ice making machines as described above, the water from the water tank is circulated by the water pump to be supplied to the ice forming surface of the upright plate. When an amount of detergents is put into the water tank, the ice forming surface of the upright plate can be washed by the detergent water supplied thereto from the water tank in operation of the water pump. In this instance, however, the evaporator on the opposite surface of the upright plate may not be washed by the detergent water circulated by the water pump.